eCryptfs: Replace miscdev read/write magic numbers

ecryptfs_miscdev_read() and ecryptfs_miscdev_write() contained many
magic numbers for specifying packet header field sizes and offsets. This
patch defines those values and replaces the magic values.

Signed-off-by: Tyler Hicks <tyhicks@canonical.com>

1 files changed, 5 insertions, 0 deletions

diff --git a/fs/ecryptfs/ecryptfs_kernel.h b/fs/ecryptfs/ecryptfs_kernel.h
index a9f29b12fbf2..a2362df58ae8 100644
--- a/fs/ecryptfs/ecryptfs_kernel.h
+++ b/fs/ecryptfs/ecryptfs_kernel.h
@@ -151,6 +151,11 @@ ecryptfs_get_key_payload_data(struct key *key)
                                           * dentry name */
 #define ECRYPTFS_TAG_73_PACKET_TYPE 0x49 /* FEK-encrypted filename as
                                           * metadata */
+#define ECRYPTFS_MIN_PKT_LEN_SIZE 1 /* Min size to specify packet length */
+#define ECRYPTFS_MAX_PKT_LEN_SIZE 2 /* Pass at least this many bytes to
+                                     * ecryptfs_parse_packet_length() and
+                                     * ecryptfs_write_packet_length()
+                                     */
 /* Constraint: ECRYPTFS_FILENAME_MIN_RANDOM_PREPEND_BYTES >=
  * ECRYPTFS_MAX_IV_BYTES */
 #define ECRYPTFS_FILENAME_MIN_RANDOM_PREPEND_BYTES 16